Background Chronic obstructive pulmonary disease (COPD) is an inflammatory disease that is characterized by a progressive and irreversible decline in lung function and is caused primarily by chronic exposure to tobacco and to wood smoke. It is linked to oxidative stress and to an up-regulation of airway arginases and is also associated with alterations in platelets and erythrocytes. In the present study, arginase activity was studied in platelets and erythrocytes of 2 groups of COPD patients: 31 tobacco ex-smokers and 27 patients who had been exposed to wood smoke. A total of 15 healthy controls were also included.

Methods Plasma, platelets, and erythrocytes were obtained from the blood samples. Levels of the oxidative stress biomarkers, carbonyls and malondialdehyde, were measured in the plasma, and arginase activity was quantified in platelets and erythrocytes.

Results In both groups of COPD patients, an increase in the oxidative stress biomarkers was found. Platelet arginase activity in both COPD groups was 2-fold higher than that in the control group. In the erythrocytes, the arginase activity increased 1.7-fold over the control only in the wood smoke-induced COPD group.

Discussion and Conclusions These results suggest that the increase in arginase activity in platelets and erythrocytes participates in the alteration in nitric oxide metabolism in COPD patients and that there may be some differences between the tobacco smoke- and wood smoke-induced COPD.

• The Surgeon General has determined that there is no safe level of exposure to ambient smoke!

• If you smell even a subtle odor of smoke, you are being exposed to poisonous and carcinogenic chemical compounds!

• Even a brief exposure to smoke raises blood pressure, (no matter what your state of health) and can cause blood clotting, stroke, or heart attack in vulnerable people. Even children experience elevated blood pressure when exposed to smoke!

• Since smoke drastically weakens the lungs' immune system, avoiding smoke is one of the best ways to prevent colds, flu, bronchitis, or risk of an even more serious respiratory illness, such as pneumonia or tuberculosis! Does your child have the flu? Chances are they have been exposed to ambient smoke!